It is frequently required in the manufacture of electronic equipment to provide switch devices on circuit boards between conductors on one surface of the circuit board. Usually, such devices comprise two or more separate metal parts such as a spring arm and a contact post which must be individually assembled to the circuit board. U.S. Pat. No. 4,144,430 shows one type of stamped and formed switch device comprising a separate cantilever spring which is mounted on the circuit board in a manner such that its free end will engage a terminal post also mounted on the circuit board.
It would be desirable to produce sheet metal switch devices as one-piece parts rather than as two-piece parts which could be directly inserted into circuit board holes so that the entire switch would be produced as a result of the single insertion operation. The present invention is directed to the achievement of such a one-piece switch device in strip form so that individual switch devices can be assembled to circuit boards by suitable automatic or semi-automatic insertion machinery.
A preferred embodiment of the invention comprises a switch which is normally closed after application to the circuit board and which has an elongated flat base having mounting tab and mounting post means extending from the ends thereof. An integral flange is provided on an end of the base and extends in the opposite direction from the direction of the mounting tabs. A spring arm is integral with the base at the remaining end, the opposite end from the end on which the flange is located, and extends beside the base portion past the flange. This spring arm has a resilient bias towards the flange but prior to insertion of the switch device has been mounted on the circuit board and the mounting tabs or posts have been soldered to the circuit board conductors, an intermediate portion of the base is removed so that the flange is electrically isolated from the remaining portions of the base. The stop is also removed and the spring arm, under the influence of its pre-stressed condition, moves against the flange thereby to complete a circuit between the conductors to which the mounting posts are soldered. The spring arm can be flexed away from the flange when it is desired to interrupt the circuit.